Electrical cabinet and a frame therefor

ABSTRACT

An electrical cabinet and a frame therefor, wherein the frame comprises side members connected together by transverse members. Each transverse member is made from bars or tubes in a skeletal form with at least one recess in the side of the transverse member. The skeletal form of each transverse member makes it cheap to manufacture and can provide for large recesses, thereby facilitating cable access. The electrical cabinet comprises removable side panels and a door mounted on the frame. The frame can also provide mounting points for subracks of electrical or electronic components.

This application is a national phase of International Application No.PCT/GB99/04394 filed on Dec. 23, 1999 and published in English underPublication No. WO 00/41283.

This invention relates to frames for electrical cabinets and toelectrical cabinets.

BACKGROUND

Electrical cabinets for receiving electronic and electrical components,are used in connection, for example, with the operation of local datanetworks. The components, for example, subracks with electronic andelectrical components, fans and other accessories are mounted within thecabinets on internal frames. The cabinets generally have side panels, adoor and end panels that surround and are mounted on the frame.

These electrical cabinets require access for cables, which are oftenthick and unwieldy, and also for people to service the appliances.Conventional frames have-substantial die-cast end members. One frame ofthe prior art is designed with end members that have recesses in thesides, these recesses can be used for cable access so that, with theside panels of the cabinet removed, cables do not need to be threadedthrough access holes. Despite the advantages of side recesses these endmembers are nevertheless, bulky, expensive to manufacture and the spacefor the cables is limited.

SUMMARY

According to one aspect of the invention there is provided a frame of anelectrical cabinet, said frame comprising:

two transverse members disposed at opposite ends of the frame andconnected together by at least two side members, each of the transversemembers having a skeletal form comprising at least one tube and/or barwith at least one side of each transverse member having a recess in asubstantial part of said at least one side.

The device of the present invention overcomes or at least alleviates theproblems of the prior art by providing transverse members which areskeletal in form, making them cheap to manufacture. The skeletal formalso provides for large recesses which allow good cable access and alsoenable service personnel to place their feet inside the cabinet givingthem better access to the electronic equipment they are servicing. Thusthe present invention can provide a frame for an electrical cabinet withimproved performance and at approximately two thirds of the price of theframes of the prior art.

Advantageously, the frame has four of the side members. The provision offour side members and transverse members at either end of the frame canprovide a robust construction for the frame.

In preferred embodiments, the transverse member is formed from two barsor tubes connected together. Advantageously, these two bars or tubeshave the same shape and are connected at and around points half wayalong their respective lengths. The use of bars or tubes havingsubstantially the same shape reduces manufacturing costs.

The tubes or bars may, advantageously, be substantially “U” shaped andmay be connected together at the bases of the two “U”s. This provides arobust shape from a small amount of material. It also provides largerecesses in the sides which are convenient for cable and personnelaccess.

In some embodiments, the base of the “U” shaped bars or tubes aresubstantially straight. This arrangement allows for the two bars to bemore easily and robustly joined together. This is particularly so ifthey are welded or brazed together. Welding and brazing provide aconvenient, strong and cost effective way of joining the two components.

In an alternative embodiment, the bars or tubes are joined to form asubstantially cross shape, preferably an elongate cross shape whereinthe end portions of one side of said elongate cross is parallel to theother side. This arrangement also provides for large side recesses.

In some embodiments, the transverse member may comprise furtherstrengthening bars or tubes connected to both of said two tubes or bars.

According to another aspect of the invention, there is provided anelectrical cabinet comprising a frame as described above and furthercomprising removable side panels, end panels and/or doors. Electricalcabinets may require the various components to be interchanged orserviced and therefore the provision of side and end panels that areeasily removable is very convenient. Although these panels and doors maybe screwed on, in preferred embodiments they are attached to the frameby hooks thereby facilitating their removal.

Although the side panels may be mounted directly to the frame, in someembodiments they are mounted on cantilevers extending out from theframe. This arrangement allows for extra space at the sides of thecabinet.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described, by way ofexample only, and with reference to the accompanying drawings, in which:

FIG. 1 illustrates a frame according to an embodiment of the presentinvention;

FIG. 2 illustrates the frame of FIG. 1 with associated side and endpanels and a quick-release door;

FIG. 3 illustrates a portion of an electrical cabinet according toanother embodiment of the present invention;

FIG. 4 illustrates a transverse member for a frame according to anembodiment of the present invention.

DETAILED DESCRIPTION

FIG. 1 illustrates a frame according to an embodiment of the presentinvention. The frame 10 comprises tubular side members 20, connectedtogether by two tubular transverse members 30 at either end of the sidemembers. The tubular transverse members comprise two straight based “U”shaped tubes 32, 34 welded together. Although in preferred embodimentsthe transverse member is comprised of tubular members welded together itmay alternatively be formed of bars, and the two pieces may be crimpedor screwed together.

FIG. 2, illustrates side panels 40, an end panel 50 and a removable door60 that are mounted on the frame of FIG. 1 to form an electricalcabinet. The removable door is mounted via hooks 62 in holes (not shown)on the side members 20 of the frame 10, thereby forming a quick-releasefitting. The end panel 50, has a ventilation hole 52, and cable accessrecesses 54. Electrical cabinets typically have a width of 19″(approximately 48 cm). They are often mounted on wheels (not shown) forease of movement.

FIG. 3 illustrates a view of a portion of an electrical cabinet 70according to an embodiment of the present invention. This electricalcabinet 70 has no end member. Electrical cabinets that are the sameheight as the room in which they are located, with cabling coming downfrom the ceiling, are often used, such electrical cabinets generallyhave no end members. In this embodiment the side panels 40 haveventilation holes. The side members 20 of the end frame comprise holes22 which receive hooks attached to elements to be mounted in theelectrical cabinet.

FIG. 4, illustrates an alternative embodiment of the transverse member30 of the frame. This member is—formed of two main bars or tubularmembers 36 welded together to form an elongate cross shape. Additionalstrengthening bars or tubes 38 may be used to support the structure.Although it is preferred to weld or braze the two portions together theymay also be attached by crimping, or by screw attachments.

1. A frame for an electrical cabinet comprising: a first and a secondtransverse member, each of the transverse members comprising: a basesection generally parallel to the front of the frame and spaced a depthfrom the front; a first, a second, a third, and a fourth lateral armsection, each of the lateral arm sections being substantiallyperpendicular to the base section; and a connecting section couplingeach of the lateral arm sections to the base section so as to truncatean inside corner formed between the arm sections and the base section atan intersection of axes of the arm sections and the base section so asto form an angle of greater than ninety degrees between the connectingsection and each of the axes of the base and the arm section; and atleast a first and a second side member, each of the side membersextending from at least one of the lateral arm sections of the firsttransverse member to an opposing lateral arm section of the secondtransverse member, wherein the first and second transverse membersdefine opposite ends of the frame relative to the side members.
 2. Theframe for an electrical cabinet according to claim 1, wherein each ofthe transverse members comprises bars or tubes.
 3. The frame as definedin claim 1, wherein each of the transverse members comprises a first anda second U-shaped member, each of the U-shaped members comprising a basemember forming a portion of the base section, two of the first, second,third, and fourth lateral arm sections, and the connecting sectionscoupling the base member of the U-shaped member to the lateral armsections, and wherein the base member of the first U-shaped member isaligned with and coupled to the base member of the second U-shapedmember to form the base section of the transverse member.
 4. The framefor an electrical cabinet according to claim 3, wherein the side memberscomprise bars or tubes.
 5. The frame for an electrical cabinet accordingto claim 3, further comprising removable side panels which form acabinet.
 6. The frame for an electrical cabinet according to claim 5,wherein the removable side panels and/or a removable door are removablyattached to the side members of the frame by hooks.
 7. The frame for anelectrical cabinet according to claim 3, further comprising at least oneremovable door.
 8. The frame for an electrical cabinet according toclaim 3, further comprising at least one removable end panel.
 9. Theframe as defined in claim 3, wherein the first U-shaped member comprisesthe first and third lateral arm sections and the second U-shaped membercomprises the second and fourth lateral arm sections and wherein thefirst lateral arm section of the first U-shaped member is substantiallyparallel to the second lateral arm section of the second U-shaped memberin each transverse member, and wherein the third lateral arm section ofthe first U-shaped member is substantially parallel to the fourthlateral arm section of the second U-shaped member in each transversemember.
 10. The frame as defined in claim 9, further comprising a thirdand a fourth side member, and wherein the first, second, third andfourth side members each extend from an outer edge of one of the lateralarms in the first transverse member to an outer edge of an opposinglateral arm in the second transverse member.
 11. The frame as defined inclaim 3, wherein the base member of the first U-shaped member is weldedto the base member of the second U-shaped member.
 12. The frame asdefined in claim 3, wherein the connecting sections are angled withrespect to the base section and the lateral arm section.
 13. A frame foran electrical cabinet, comprising: a first and a second transversemember, each of the transverse members comprising: a first and a secondU-shaped member, each of the first and second U-shaped memberscomprising a base, a first and a second lateral arm section provided atopposing ends of the base and a connecting section coupling each of thelateral arm sections to the base section so as to truncate a cornerformed at an intersection of axes of the arm sections and the basesection, wherein the base of the first U-shaped member is aligned withand coupled back-to-back to the base of the second U-shaped member suchthat the first and second lateral arm sections of the first U-shapedmember extend parallel to and away from the second and first lateral armsections of the second U-shaped member, respectively; and at least afirst and a second side member, each of the first and second sidemembers extending between the first transverse member and the secondtransverse member on opposing sides of the transverse members, whereinthe first and second side members extend from an outer edge of thelateral arm section of the first transverse member to an outer edge ofthe lateral arm section of the second transverse member such that thefirst and second transverse members define opposing ends of the frame.14. The frame as defined in claim 13, wherein at least one of theconnecting sections is angled.
 15. The frame as defined in claim 13,further comprising at least one removable side panel coupled to the sidemembers.
 16. The frame as defined in claim 13, wherein the first andsecond U-shaped members are constructed from tubes.
 17. The frame asdefined in claim 13, wherein the first and second U-shaped members areconstructed of bars.